A's players mob closer Grant Balfour after the final out in their game against the Rangers. The Oakland Athletics clinched a playoff spot on Monday, October 1, 2012, after they defeated the Texas Rangers at O.co Coliseum in Oakland, Calif.

OAKLAND, CA - OCTOBER 01: Brandon Moss #37 of the Oakland Athletics is congratulated by teammates after he hit a sacrifice fly that scored Coco Crisp #4 of the Oakland Athletics in the fifth inning of their game against the Texas Rangers at O.co Coliseum on October 1, 2012 in Oakland, California. (Photo by Ezra Shaw/Getty Images)

Photo: Ezra Shaw, Getty Images

OAKLAND, CA - OCTOBER 01: Brandon Moss #37 of the Oakland...

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OAKLAND, CA - OCTOBER 01: Sean Doolittle #62 of the Oakland Athletics pitches against the Texas Rangers at O.co Coliseum on October 1, 2012 in Oakland, California. (Photo by Ezra Shaw/Getty Images)

Photo: Ezra Shaw, Getty Images

OAKLAND, CA - OCTOBER 01: Sean Doolittle #62 of the Oakland...

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Oakland Athletics fans perform the Wave during their MLB baseball game with the Texas Rangers in the 7th inning Monday October 1, 2012 in Oakland California

Photo: Lance Iversen, The Chronicle

Oakland Athletics fans perform the Wave during their MLB baseball...

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OAKLAND, CA - OCTOBER 01: Jarrod Parker #11 of the Oakland Athletics pitches against the Texas Rangers at O.co Coliseum on October 1, 2012 in Oakland, California. (Photo by Ezra Shaw/Getty Images)

Photo: Ezra Shaw, Getty Images

OAKLAND, CA - OCTOBER 01: Jarrod Parker #11 of the Oakland...

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OAKLAND, CA - OCTOBER 01: Brandon Moss #37 of the Oakland Athletics hits a sacrifice fly that scored Coco Crisp #4 of the Oakland Athletics in the fifth inning of their game against the Texas Rangers at O.co Coliseum on October 1, 2012 in Oakland, California. (Photo by Ezra Shaw/Getty Images)

Oakland Athletics pitcher Jarrod Parker (11) waits for Texas Rangers' Michael Young to run the bases after Young hit a home run in the fourth inning of a baseball game, Monday, Oct. 1, 2012, in Oakland, Calif. (AP Photo/Ben Margot)

Photo: Ben Margot, Associated Press

Oakland Athletics pitcher Jarrod Parker (11) waits for Texas...

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Oakland Athletics' Jarrod Parker works against the Texas Rangers in the first inning of a baseball game, Monday, Oct. 1, 2012, in Oakland, Calif. (AP Photo/Ben Margot)

Photo: Ben Margot, Associated Press

Oakland Athletics' Jarrod Parker works against the Texas Rangers in...

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OAKLAND, CA - OCTOBER 01: The Oakland Athletics celebrates after the Athletics beat the Texas Rangers to clinch a playoff spot at O.co Coliseum on October 1, 2012 in Oakland, California. (Photo by Ezra Shaw/Getty Images)

Photo: Ezra Shaw, Getty Images

OAKLAND, CA - OCTOBER 01: The Oakland Athletics celebrates after...

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OAKLAND, CA - OCTOBER 01: Grant Balfour #50 of the Oakland Athletics celebrates after the Athletics beat the Texas Rangers to clinch a playoff spot at O.co Coliseum on October 1, 2012 in Oakland, California. (Photo by Ezra Shaw/Getty Images)

Photo: Ezra Shaw, Getty Images

OAKLAND, CA - OCTOBER 01: Grant Balfour #50 of the Oakland...

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OAKLAND, CA - OCTOBER 01: Grant Balfour #50 of the Oakland Athletics celebrates after the Athletics beat the Texas Rangers to clinch a playoff spot at O.co Coliseum on October 1, 2012 in Oakland, California. (Photo by Ezra Shaw/Getty Images)

Photo: Ezra Shaw, Getty Images

OAKLAND, CA - OCTOBER 01: Grant Balfour #50 of the Oakland...

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OAKLAND, CA - OCTOBER 01: The Oakland Athletics celebrates after the Athletics beat the Texas Rangers to clinch a playoff spot at O.co Coliseum on October 1, 2012 in Oakland, California. (Photo by Ezra Shaw/Getty Images)

Oakland Athletics celebrate after clinching a wild card berth in the American League at the end of a baseball game against the Texas Rangers on Monday, Oct. 1, 2012, in Oakland, Calif. (AP Photo/Ben Margot)

Photo: Ben Margot, Associated Press

Oakland Athletics celebrate after clinching a wild card berth in...

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Oakland Athletics players celebrate after clinching a wild card berth in the American League at the end of a baseball game against the Texas Rangers on Monday, Oct. 1, 2012, in Oakland, Calif. (AP Photo/Ben Margot)

Photo: Ben Margot, Associated Press

Oakland Athletics players celebrate after clinching a wild card...

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A's players emerge from the dugout after the final out in their game against the Rangers. The Oakland Athletics clinched a playoff spot on Monday, October 1, 2012, after they defeated the Texas Rangers at O.co Coliseum in Oakland, Calif.

Photo: Carlos Avila Gonzalez, The Chronicle

A's players emerge from the dugout after the final out in their...

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Oakland Athletics' Grant Balfour celebrates after the team clinched a wild card berth in the American League at the end of a baseball game against the Texas Rangers Monday, Oct. 1, 2012, in Oakland, Calif. (AP Photo/Ben Margot)

Photo: Ben Margot, Associated Press

Oakland Athletics' Grant Balfour celebrates after the team clinched...

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A's players mob closer Grant Balfour after the final out in their game against the Rangers. The Oakland Athletics clinched a playoff spot on Monday, October 1, 2012, after they defeated the Texas Rangers at O.co Coliseum in Oakland, Calif.

Photo: Carlos Avila Gonzalez, The Chronicle

A's players mob closer Grant Balfour after the final out in their...

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The Champagne was spraying all over the A's clubhouse after the clinching win over the Rangers on Monday night.

Photo: Lance Iversen, The Chronicle

The Champagne was spraying all over the A's clubhouse after the...

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A's players mob Grant Balfour after the closer from Australia struck out Texas' Mike Napoli for the final out.

Photo: Carlos Avila Gonzalez, The Chronicle

A's players mob Grant Balfour after the closer from Australia...

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Oakland Athletics starting pitcher Jarrod Parker works in the third inning of their MLB baseball game against the Texas Rangers Monday October 1, 2012 in Oakland California

Photo: Lance Iversen, The Chronicle

Oakland Athletics starting pitcher Jarrod Parker works in the third...

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Texas Rangers catcher Mike Napoli catches his breath in the fifth inning after being hit by a pitch during their MLB baseball game with the Oakland Athletics Monday October 1, 2012 in Oakland California

Photo: Lance Iversen, The Chronicle

Texas Rangers catcher Mike Napoli catches his breath in the fifth...

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A fan tries to get the crowd fired up as the A's played the Rangers in the final innings. The Oakland Athletics clinched a playoff spot on Monday, October 1, 2012, after they defeated the Texas Rangers at O.co Coliseum in Oakland, Calif.

Photo: Carlos Avila Gonzalez, The Chronicle

A fan tries to get the crowd fired up as the A's played the Rangers...

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Dylan Collier of Richmond, reacts as the final out is called and the A's clinched a playoff spot for the first time in six years. The Oakland Athletics clinched a playoff spot on Monday, October 1, 2012, after they defeated the Texas Rangers at O.co Coliseum in Oakland, Calif.

An improbable, implausible, absurd season for the Oakland A's churned out one sensational story after another, and at last comes the most fantastic tale yet:

The 2012 A's are going to the postseason.

Yes, the club that traded three of its top pitchers, all All-Stars, last winter. The team that lost its starting third baseman on the first full day of spring training and three starting pitchers in the past month and a half.

Oakland's third baseman is a catcher, the first baseman is an outfielder, the former shortstop is at second base and the top left-hander in the bullpen was a first baseman until last fall, for crying out loud. There are five rookies in the A's rotation. Five of them.

Yes, this group of castoffs and youngsters beat the two-time defending AL champion Rangers 4-3 Monday night at the Coliseum to claim, at the least, the second wild-card spot. The team celebrated with a sight familiar in its home park: wildly jumping around in a tight bunch.

"We've shocked the world," said Monday's winning pitcher, Jarrod Parker, one of the rookie five. "And we're not done."

The victory also kept Oakland's hopes alive in the AL West: The A's are one game behind Texas with two games to play.

"We've silenced a lot of critics to come this far," A's right fielder Josh Reddick said, Champagne dripping off his hat as he spoke. "It's a great feeling. ... We're ready to celebrate two days from now, too."

Reddick is the designated pie-thrower after the team's league-leading 14 walk-off wins, slapping a dish of whipped cream on the hero of the evening. Monday's win didn't come in the last at-bat, but Reddick designated a hero: manager Bob Melvin, whose club has 92 victories and is a season-high 24 games over .500.

"I never had the opportunity to get him before," Reddick said. "That was the perfect setup."

"I didn't expect that," Melvin said of the sugary face-wash. "I did turn around quickly for the Gatorade buckets and there weren't any, so I was glad about that."

Oakland clinched a spot in the way every team would want: The A's did it with a win, rather than backing in. In fact, they had to win in order to grab the playoff spot Monday, because the Rays and Angels both won.

The Angels, now out of the postseason, spent more than $330 million on two players, Albert Pujols and C.J. Wilson, last offseason. The A's have the lowest payroll in the league, but they were not to be denied.

Coco Crisp had two hits, scored two runs and drove in one. He did one of each of those things in the fifth inning, plus stole a base, to help give the A's the lead after Texas had tied it 2-2. He followed Adam Rosales' double with one of his own, sending in Rosales to put Oakland up 3-2, then he stole third, and with one out, he raced home on a shallow flyball by pinch hitter Brandon Moss.

"When you're playing a team like that, every run counts," Moss said. "You have to play aggressive. As long as he was safe, I don't care, because I didn't hit it that good."

That proved to be a key bit of insurance when Mike Napoli hit a solo homer off Parker in the seventh. Parker came out after that blast to center. The rookie finished the regular season 13-8 with a 3.47 ERA - and he went 13-0 in games in which he got at least two runs of support.

Moss exemplifies the A's season: He signed as a minor-league free agent and he has hit 21 homers in 83 games since coming to the big club in June. He has hit more homers than any Oakland first baseman since Jason Giambi in 2001.

"We have a great group; every single guy in the clubhouse has contributed," he said. "We have a lot of players who've been told 'No,' and when you put guys like that together, there's a lot of fight in them."